Công tắc tốc độ băng tải, Slip detector DH-RD-II ,RD-I RD-II RD-DH-III

Working principle :
The main difference between a rotary detector and a proximity switch is that it has a delay circuit inside. It can be different from a passive axis. The main difference between a rotary detector and a proximity switch is that it has a delay circuit. It can adjust the internal speed according to the different speeds of the passive axis. The delay time is reached to protect the equipment from jamming. The rotation detector is installed on the passive shaft. As shown in Figure 1, he uses the detection piece installed on the driven shaft to use the principle of electromagnetic induction to give a speed switch pulse signal (when the detection piece It is a pulse when turning to a distance of 4-8 millimeters from the speed switch . Take Figure 1 as an example: when the power is turned on, the speed switch makes the relay pull-in delay for a set number of seconds through a series of relays. The passive axis of the device rotates once Need to give two pulses to the speed switch. If the speed switch is set to 8 seconds, the device rotates one revolution for less than 8 seconds, the speed switch does not operate through the serially connected relays (relays stay on), and when the device rotates for more than 8 seconds, The speed switch believes that a stall has occurred. The relay is tripped ( relay de-energized ) through a series of relays to protect the equipment.
Features:
● Non-contact, no moving parts, no wear, long safety life, low maintenance costs, suitable for harsh environments. 
● Integrated structure, no setup, no debugging, easy installation. 
● Small size, light weight and long life 
● With load short-circuit protection function - connecting the rotary detector to the power supply by mistake will not damage the rotary detector. ( Not more than 1 minute ) 
● The output signal can be used in interlocking with field equipment or sent to the DCS control system 
● Equipped with status indicator. When the device is running normally, the indicator light is “blinking”; when the device is stopped, the indicator light is “always on”. 
Technical Specifications:

 
Installation Notes:
All transmission devices, such as screw conveyors, elevators, belt conveyors, zippers, crushers, etc., should be installed at the driven shaft ( end of the machine ) .
 
 
Note: The installation position of the rotation speed monitor in the installation diagram depends on the specific situation. You don't need to stick to this figure. As long as it does not affect the normal work, you only need to meet the condition of "pulse signals uniformly spaced to the probe within a unit time." .
 
 
Mechanical installation process:
1. Remove the end cover, drill ≥ Φ 12 holes in the center of the end cover, drill Φ 5.1 holes in the bottom of the end cover , tap M6 ( matching processing with the two holes of the rotation speed monitor bracket ) , and fix the end cover and bracket with screws
2. Drill Φ 5.1 hole in the shaft head , tap M6 , 10 ~ 15mm deep
3. Tighten the double-headed screw
4 , install the end cap
5. Install the test piece, F ≥ 20mm and fix it with nuts
6. Install a rotation speed monitor and adjust G = 4mm.  Some machines have longer driven shafts and extend beyond the end cover. For such cases, you only need to make the test piece into a round shape and fix it on the shaft head ( please note The plane of the test piece is kept parallel to the plane of the probe of the rotation speed monitor. If it is installed on a metal base, in order to prevent the equipment from starting due to strong interference of magnetic materials, please pay special attention to the distance of F ) .
Electrical wiring: RT type rotation speed monitor and intermediate relay are used in series (see electrical wiring diagram). The intermediate relay coil withstands 220V .
Test piece: The material is ordinary iron sheet, the number of leaves is 2 leaves, and the size of the test piece is 100 × 10 × 2mm .
Reference formula for trip time: T (trip time)> [ 60 seconds × 3 (constant value)] ÷ [number of detected pieces × number of driven revolutions]
 
Wiring: